Lock for elevator doors



March 13, 1928.

J. A. SCHWEIG LOOK FOR ELEVATOR DOORS Filed Oct. 1., 1926 4 Sheets-Sheet l March 13; 1 928.

1,662,342 J. A. SCHWEIG LOOK FOR ELEVATOR DOORS 7 Filed on. 1, 1926 4 Sheets-Sheet 2 /0 firrozmexs.

March 13, 1928. 1,662,342

. J. A. SCHWEIG LOCK FOR ELEVATOR DOORS Filed Oct. 1, 1926 4 sheets-she 3 fig. .5.

& 6

Patented Mar. 13, 1928.

JULIUS A. SCHVEIG, OF ST; LOUIS, MISSOURI.

LOCK FOR ELEVATOR DOOR-S.

Application filed October 1,1926. Srial No 138,866.

This invention relates to locks for elevator doors. One of the principal objectsof the invention is to devise a cheap and ellicient lock which will prevent the opening of the elevator doors when the car is not at a landing and which will prevent the operation of the elevator until all the doors inthe shaft are closed and locked. Another object. is to prevent the look from being tampered with when the door is open. Other objects are simplicity of construction, ease of assembly and installation, and compactness and economy of design. The invention consists in the combinations and arrangements of parts hereinafter described and claimed.

In. the accompanying drawings which form part of this specification and where n like symbols refer to like parts wherever they occur,

Fig. 1 is an interior view of a portionof an elevator shaft at one of the door openings, showing a locking device embodying my invention mounted in the shaft in position to cooperate with the latch bar of avertical sliding door;

Fig. 2 is an enlarged face view of the lock and the parts associated therewith, the cover plate of the lock being shown removed and the lock being shown in locked position;

Fig. 3 is a view similar to Fig. 2, the lock being shown in unlocked position;

Fig. d is a horizontal section through one side of the door opening on the line 44 in Fig. 1;

Fig. 5 is a vertical section through the door opening showing the position of the parts when the car is at the landing and the vertically sliding doors are partly open;

Fig. 6 is a view similar to Fig. 5 showing the positions of parts after the car has left the landing and the doors are closed;

2 Fig. 7 is a vertical sect-ion through the lock on the line 7-7 invFig. 3; and

Fig. 8is a view similar to Fig. 2showing a modified form of locking device.

Referring to Figs. 1 to 7, inclusive, of the accompanying drawings, my invention is shown in connection with the shaft 10, car or cagell, and the vertically sliding upper and lower door sections or gates 12 and 13 of an. electrically operated freight elevator. As shown in the accompanying drawing, the upper and lower metal clad sliding door sections 12 and 13 for each door opening in the elevator shaft are provided along each vertical edge with an angle bar frame member 14. slidably arranged between angle bar guides 15 that are rigidly secured to each other and to the adjacent jamb members 16 of the door openin The upper and lower door sections arecounterbalanced by means of chains 17 suitably connected to the lower corners of the upper door section 12. Said chains extend upwardly around pulleys (not shown) and are connected to the upper ends of upright chain rods 18, whose lower ends are secured to the upper corners'of the lower door section 13 by means of door arms 18 that project horizontally therefrom. V

The door is provided with a latching device comprising an operating lever 19, which is pivotally mounted for, vertical swinging movement on the inner side of the lower door sectionll near the middle of its upper end portion, and oppositely extending horlzontally slidable latch bars 20 and 20, whose inner ends are pivotally connected to the respective upper and lower arms of the open ating lever. The free outer: ends of the-latch bars are adapted to be slidably supported on the lower door section and slid beyond the side edges of said section into engagement with suitable catches provided therefor at the sides of. the door opening when the up-.

per or handle end of operating lever is swung upwardly. One end of a coil spring 21 is attached toone of the latch bars and its other end is secured to a bracket 22 riveted to the inner surface of the lower door section, the parts being arranged so that the spring tends to exert an outward pull on. the latch bar and thus normally tends to hold the same in its latched position; The constructionof elevator thus far described is well known and it is considered unneces sary to illustrate it in detail.

The outer end of thehorizontally slidable latch bar 20 is provided at its upper edge with. a notch 23 forming a hooked end poi tion adapted, in the latched position of the latch bar, for cooperation witha locking device, which prevents unlocking of the door ltttClllllQ device when the elevator car is not at aolanding and. which also prevents the operation of the electric elevator until all the doors in the elevator shaft are closed and locked. Said locking device comprises a hollow casing 24; which is bolted or other wise rigidly secured to one of the angle bar door guides 15 in position to cooperate with the notched outer end of the latch bar 20. The side of the casing which faces the notched end of the latch bar 2U is provided with an opening 2t" adapted to receive the,

hooked end of said latch bar; and inner face of said casing is provided with an opening which is closed by means of a removable cover plate 25. l'ivotally mounted in the lock casing for vertical swinging movement towards and away from the outer end of the latch bar :20 is an upright arm 26. The lower end ol said arm is journaled on a horizontal pivot 26 l'ixed to said casing. Disposed between the inner edge of the arm 26 and a lug 27 on the casing is a coil spring 28 which operates to swing the upper end of said arm in the direction of the latch bar :20. Rigidly secured to the inner or rear edge of the arm it of the lock is a fiber insulating: block it), which carries a pin 25) upon whose outer end sleeved a contact plate 30. The contact plate 3t], which forms one element of an electric switch, is held on the pin it) by means of a cotter pin 31; and a coil spring 32 is mounted on said pin between the insulating block 29 and said contactplate l'or yieldabty holding said plate against said cotter pin. The other element of the electric switch com n'ises a pair of posts mounted on a llber insulating block 34 secured to the rear side wall ot the lock casing. The two contact members are positioned in the casing so as to be engaged by the contact plate 30 when the arm 26 which carries said plate is swung rearwardly. Said contact members 33 are provided with binding screws 33" which receive the wires of an electric circuit, (not shown) which controls the operation of the electric elevator.

Pirotally mounted in a vertical slot provided therefor in the upper end of the arm 26 is a lever or catch :35 whose outer arm terminates in a. downwardly projecting hook 36 adapted to interlock with the hooked outer end of the latch bar Qt) in the projected or latched position thereof. The inner arm ol the catch it? is adapted to abut against the top wall of the opening 2 in the casing when the latch bar is rctractetil and the arm 26 is pulled forward by said bar. thus causing the hooked end of such 'atch to swing upwardly clear of the notch in said bar after said hooked end has moved clear of said opening. \Vhen. the arm 26 is swung rearwardly by the pressure of the latch bar 20 thereagainst. the catch 35 on the upper end of said arm is carried rearwardly through the slot 2t in the lock casing. and the hooked end 36 of said catch abuts against the top wall of said slot and is thus forced downwardly into interlocking engagement with the hooked outer end of said latch bar. Mounted on a shaft 37 journaled in the upper end of the lock casing" at right angles to the horizontal pivot for the arm 26 is a downwardly projecting lock arm 38 adapted, in the rearward position of the arm :16. to swing in front of the upper end thereof and thus prevent forward swinging movement thereot'. 'lhe rocker arm 3b is automatically swung into position in front of the upper end of the arm 26 by means of a coil spring 36' sleeved on the rock shaft with one end hooked over said rock arm and with the other end hearing: against the top wall 01 the lock casing.

The rock shatt projects beyond the rear side wall of the lock casing and has a release arm fixed thereto, said arm comprising a lower or inner section 3!) tixed to rock shaft 257 and an upper or outer section 39 adjustably secured to the outer end (it the inner section and carrying a roller i at its outer end. The outer end of the l'(ltti.-t arm projects inwardly into the elevator shaft with its roller -10 disposed in the path of a cam plate ll secured to the elevator car or cage ll. This cam is located so that it engages the roller 10 of the release arm when the car is at the landing; which action rotates the rock shalt 3? and causes the rock arm 38 liXcd thereon to swing clear of the path of the arm .26. i

The upper end of the arm :20 is provided with a pin 42 which projects rearwardly through a slot l3 provided thercl'or in the rear side wall of the lock casing. in the closed position of the lockin; device. said pin project's far enough beyond the lock casing to extend into the path of the upper arm of the lever it which is pivotally secured to rear side wall ot the casing for rertical swinging;- movement at right angles to the axis of said pin. The lower arm of the lever it is counterweighted so as to cause the upper arm oi said lever to swing into the path of th arm 18: and said arm is held in a position opposite the pin l2 carri d by the arm 26 by means of a stop lug: to which is engaged by the counterweighted lower arm of said lever. In the closed positi n of the doors. the upper end ol the counterwein'httal lever ii is engaged by the door arm 18 ol the lower section. which arm operates to swim: the upper arm of the lever l-l clear of the path of the pin ii on the arm Elli. When the door is opened. the arm 15+ ol the lower section thercot' moves downwardly clear of the upper arm of the counter-weighted lever 4st. whereupon said arm of said lerer swings into a position opposite the end of the pin 42 on the arm 26 and thus 1nerents said arm from being swung rearwardly to close the electric circuit which controls the operation of the elevator.

As shown in the drawing. the lower front. corner of the lock casing is provided with a beveled surface 46. which engaged by the outer end of the latch bar 20 during the closing mm'lm'ienl' of tile lower door Section and causes said bar to slide inwardly against the pressure of the spi'ing'21. The latch bar is held in its retracted position by the lock casing until said bar reaches a position 0pposite the opening-24 in thel lock casing, in which position the hooked end of the bar is pushed into said opening into engagement with the arm 26. The outer end of the bar is supportedforfree sliding movement prererably by means of an anti-friction roller 47 journaled in the bracket 48 fixed to the inner side of the lower door section.

The: operation of the device is as follows:

hen the car arrives at alanding the cam fixed to the car engages the roller 4Ov at the outer end of the release lever. and causes the rock arm 38 on the rocktshaft 37 to swing clear of theupper end ofthe arm 26, which arm is prevented from outward swinging movement by the pressure exerted thereagainst by the springpressed latch bar 20. The operating lever 19. is then operated to cause the latch bar. to slide inwardly against the pressure of the spring 21,which action, due to the interlocking engagement of the hooked ends of the latch bar and the catch on the arm 26,.causessaid catch to travel outwardly through the opening 24 in the lock casing. During the outward travel of the catch 35,the upwardly inclined inner arm thereof abuts against. the lock casing and is forced downwardly, thereby causing the hook 36 on the outer arm of said catch to swing upwardly out of engagementwith the hook at the outer end ofthe. latch bar. The counterweighted door sections are then separated by a downward pressure on the lower door section, which action causesthe door arm 18 at the upper corner of. the lower section to move clear of the upper arm of the cor.nterweighted stop lever 44 and thus permit said arm toswing in front. of the pin 42 carried by the arm 26, thereby preventing rearward movement of thelever. This outward movement of. the. catch 35 causes the arm 26 whichsupports said catch to swing. outwardly,-which action breaks the contact betweeir the. contact plate 30 carried by said arm and the posts 33 mounted on the casing and thus opens the electric circuit which controls the operation of the elevator.

W'hen the doors are closed, the door arm 18 swings the counterweighted lever 44 clear of the pin 42 on the a1'm26, and: the latch bar 20 is automatically slid into'abutting relation with the saidarn'nin which position the notch 23 in said latch bar is directly beneath the hooked endSG of the catch 35cmried by said arm. Further outward sliding abuts against the upper edge of said. opening rangements shown and described.

andiis swung downwardly into engagement with the hooked outer end 01" the latch bar. Inthis position of the catch 85, the pin 42 at the upper end of the catch supporting arm 26 swings in front of the counterweighted lock lever 44 and the contact plate 30 on the arm 26 bears against the contact members 83 mountedon the casing, thereby closing the electric circuit or the elevator and thus permitting the operation thereof. The car may then leave the landing, whereupon the cam 41 thereon moves out of en gagement with the roller carried by the release lever and permits the shaft 37 to be rotated by the action of the spring 38 and move the lock arm 38 into the path of the arm 26 and thus prevent unlocking of the elevator doors until the car again reaches the landing.

In the modified construction shown in Fig. 8, the counterweighted arm, which prevents tampering with the lock inthe opened position thereof, and the parts actuated by the cam on the elevator to prevent unlocking oi' the parts until the elevator reaches the landing, are omitted. In this construction, the locks are attached to each door, and are connectedin. seriesto the elevator controller board, so that the elevator cannot be operated until all doorsin the shaft are closed and latched. V

The hereinbefore described arrangement admits of considerable modification, and I do not wish to be limited tothe precise ar- VVhat I claim is a a 1. In an electric elevator, asha'lt, a car working therein, doors for closingthe door openings in said shai t, latch bar foreach door, a catch arranged to move into engagement with said latch barfiwhen the same is loo moved to latched position, a switch tormaking and breaking anelectric circuit for controlling. the operationoi' the elevator car, means whereby said switch is automatically actuated to close thecircuit in the engaged position of said latch bar and said catch door is open.

2. In an electric elevator, a shaft, a car,

working therein, doors for closing the door openings in said shaft, a latch bar for each door, a catch arranged to move into engage nicnt with said latch bar when the same is moved to latched position, a switch for making and breaking an electric circuit for controlling the operation of the elevator car, means whereby saidswitch is automatically actuated to closethe circuit in the engaged position of said latch bar and said catch and is automatically opened in the disengaged position thereof, and means for preventing the closing of said switch when the door is open 3. In an electric elevator, a shaft, :1 car working therein, doors for closing the door openings in said shaft, a latch bar for each door, a catch arranged to move into engagement with said latch bar when the same is moved to latched position, a switch for mak ing and breaking an electric circuit for controlling the operation of the elevator car, means whereby said switch is automatically actuatet't to close the circuit in the engaged position or said latch bar and said catch and is automatically opened in the disengaged position thereof, means for preventing the closing of said switch when the door is open, and means releasaljile by the car at the landing for preventing disengagement of said catch from said latch bar after the 'ar leaves said landing.

-l-. An electric elevator, a shaft, a car working therein, doors for closing the door openings in said shaft, a spring projected latch bar tor each door, a lock casing secured to the shaft opposite the outer end of said latch bar, an electric switch mounted in said casing for making and breaking the electric current controlling the operation of the elevator car, an arm pivoted in said casing for swinging movement towards and away from said end of said latch bar, a catch pivotally mounted on the free end of said arm and adapted to move into interlocking engagement with said latch bar when the latter is pressed against said arm and swings it rearwardly, a spring for swinging said arm in the direction of said latch bar in the retracted position thereof, means whereby said latch is disengaged from said bar when said arm moves in said direction, and means operated by the swinging movement of said arm for closing said switch in the engaged position of said latch bar and said catch and for opening said switch in the disengaged position of said members 5. An electric elevator, a shaft, a car working therein. doors for closing the door o iienings in said shaft, a spring projected latch bar for each door, a lock casing secured to said shaft opposite the end of said latch bar and provided with an opening adapted to receive said end of said bar, an arm pivoted in said casing for swinging movement towards and away from said end of said latch bar. a catch mounted on said arm and adapted to move into engagement with said latch bar when the arm moves rearwardly under pressure of said bar. a spring for swinging said arm forwardly in the direction of said latch bar in the retracted position thereof, a switch for making and breaking the electric circuit controlling the operation oi the elevator car, and means con trolled by the swinging movement of said arm for closing said switch in the engaged position of said catch and for opening said switch in the disengaged position of said catch.

(5. An electric elevator, a shaft, a car working therein, doors for closing the door openings in said shaft, a spring projected latch bar for each door, a lock casing secured to said shaft opposite the end of said latch bar and provided with an opening adapted to receive said end of said bar, an arm pivoted in said casing for swinging movement towards and away from said end of said latch bar, a catch mounted on said arm and adapted to move into engagement with said latch bar when the armmoves rearwardly under pressure of said bar, a spring for swinging said arm forwardly in the direction of said latch bar in the retracted position thereof, a switch for making and breaking the electric circuit controlling the operation of the elevator car, means controlled by the swinging movement of said arm for closing said switch in the engaged position of said catch and for opening said switch in the disengaged position of said catch, and means for locking said catch and said switch in closed position, said locking means being adapted to be released by the ear upon arrival thereof at the landing.

7. An electric elevator, a shaft, :1 car working therein, doors for closing the door openings in said shalt, a spring, projected latch bar for each door, a lock casing secured to said shaft opposite the end of said latch bar and provided with an opening adapted to receive said end, an arm pivoted in said casing for swinging movement towards and away from said end of said latch bar, a spring normally tending to swing said arm in the direction of said latch bar, a catch mounted on said arm and adapted to move into engagement with said latch bar under pressure of the same against said arm, a switch for making and breaking the electric circuit controlling the operation of said elevator, and means operated by the swinging movement of said arm for opening said switch when the catch is discngaged jt'roni said latch bar and for closing said switch when the catch is engaged with said latch bar.

9. An electric elevator, a shaft. :1 car working therein, doors for closing the door openings in said shaft, a spring projected latch bar for each door, a lock casing secared to said shaft opposite the end of said latch bar and provided with an opening adapted to receive said end, an arm pivoted in said casing for swinging movement towards and away from said end of said latch bar, a spring normally tending to swing said arm in the direction of said latch bar. a catch mounted on said arm and adapted to move into engagement with said latch bar under pressure of the same against, said arm,

the operation of said elevator, means operated by the swinging movement of said arm for opening said switch when the catch is disengaged from said latch bar and for closing said switch when the catch is engaged with said latch bar, and means for preventing the closing of said switch when the door is open.

9. In an electric elevator, a shaft, a car working therein, doors for the door openings'in said shaft, a horizontally slidable spring projected latch bar for each door, said latch bar having an upwardly *opening notch at its outer end, a lock casing located opposite said end of said latch bar and having an opening adapted to receive the same, an arm pivoted in said casing for vertical swinging movement and adapted to be swung r-earwardly under pressure of the latch bar thereagainst, a spring normally tending to force said arm towards said latch bar, a catch pivotally supported on said arm and having a hooked end adapted to engage the notch in said latch bar when the arm is swung, rearwardly under pressure of said bar thereagainst, a switch adapted to make and break an electric circuit controlling the op eration of the elevator car, said switch being adapted to be automatically closed when said arm is swung rearwardly under pressure of said latch bar thereagainst and automatically opened when said pressure is released, and means for locking said catch and arm against movement when the car leaves the landing.

10. In an electric elevator, a shaft, a car working therein, doors for the door openings.

in said shaft, a horizontally slidable spring projected latch bar for each door, said latch bar having a hook at its outer end, a lock casing located opposite said end of said latch bar and having an opening adapted to receive the same, an arm pivoted in said casing for vertical swinging movement and adapted to swing rearwardly under pressure of the latch bar thereagainst, a spring normally tending to force said arm toward said latch bar, a catch pivotally supported on said arm and having a hooked end adapted to interlock with the hooked end of said latch bar when the arm is swung rearwardly under pressure of said bar thereagainst, means whereby said catch is automatically disengaged from said latch bar during the rearward movement thereof, a switch adapted to make and break an electric circuit controlling the operation of the elevator car, said switch being adapted to be automatically closed in the interlocked position of said catch and said latch bar and automatically opened before said members are disengaged, means for locking said catch and arm against movement when the car leaves the landing, and means for preventing the closing of said switch when the door is open.

11. In an electric elevator, a shaft, a car working therein, doors for the door openings in said shaft, a horizontally slidable spring projecting latch bar for each door, said latch bar having a roller for supporting the outer end portion of said bar, a hooked outer end, a lock casing located opposite said end of said latch bar an d having an opening adapted to receive the same, an arm pivoted in said casing for vertical swinging movement and adapted to be swung rearwardly under pressure of the hooked end of latch bar thereagainst, a spring normally tending to force said arm toward said end of said latch bar, a catch pivotally supported on said arm and having a hooked end adapted to cooperate with the hooked end of said latch bar, means for swinging the hooked end of said catch into engagement with the hooked end of said latch bar when the arm supporting said catch is swung rearwardly under pressure of said bar thereagainst, means for dis engaging the hooked ends of said catch and said bar whensaid arm is drawn forward by retraction of said bar, a switch adapted to make and break an electric current controlling the operation of the elevator car, means whereby said switch is automatically closed at the beginning of the closing movement of said catch and is opened at the beginning of the opening movement thereof, means for locking said catch and said switch in closed position when the car leaves the landing, and means for preventing the closing of said switch when the door is open.

Signed at St. Louis, Missouri, this 28th day of September, 1926.

JULIUS A. SCHWEIG. 

